Analysis of different cultivars and origins of Chinese cigar tobacco leaves based on headspace solid phase microextraction-gas chromatography-high resolution mass spectrometry combined with multivariate statistical methods.

Cigar tobacco leaves are a crucial factor influencing the quality of cigars, as they are an important component in cigar production. In this study, a novel method of headspace solid phase microextraction-gas chromatography-high resolution mass spectrometry (HS-SPME-GCHRMS) was developed for the analysis of cigar tobacco leaves via systematic evaluation of extraction techniques and chromatographic parameters. Six cultivars from Sichuan Province and one cultivar from nine geographical origins (Hubei, Hainan, Sichuan, and Yunnan) were analyzed. A total of 12 types of volatile organic compounds (VOCs) were detected from all samples, including esters, ketones, phenols, acids, alcohols, aldehydes, alkanes, terpenes, benzenoids, heterocyclics, nicotine derivatives, and others. Among these, nicotine derivatives dominated. Multivariate statistical methods such as linear discriminant analysis (LDA), principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) have been utilized to effectively discriminate between different cultivars and geographical origins of cigar tobacco leaves. A range of key differential compounds were revealed via variable importance in projection (VIP) analysis, including nicotyrine, 4,4'-bipyridine, cyperen-8-one, methyl tridecanoate and cotinine. These findings demonstrated that the VOCs of cigar tobacco leaves were significantly affected by both genotype (cultivar difference) and terroir (geography), suggesting that HS-SPME-GCHRMS coupled with multivariate statistical methods is a robust platform for varietal identification, geographical origin, and quality control in cigar tobacco leaves.